1. The Globe Valve should be installed upright and close to the protected equipment or pipeline. If it cannot be arranged close, the total pressure drop in the pipeline from the protected equipment or pipeline to the inlet of the Globe Valve should not exceed 3% of the fixed pressure value of the Globe Valve.
2. The Globe Valve should be equipped with a maintenance platform. When arranging heavy Globe Valve, the possibility of lifting the
Universal Valve after disassembly should be considered, and a suspender should be installed if necessary.
3. The inlet pipe of the Globe Valve should use a long radius elbow.
4. The design of the outlet pipeline of the Globe Valve should consider that the back pressure does not exceed a certain value of the fixed pressure of the Globe Valve. For ordinary spring-type Globe Valve, the back pressure does not exceed 10% of the fixed pressure value of the Globe Valve.
5. When the medium discharged into the vent main pipe or the flare main pipe contains condensate or condensable gas, the outlet of the Globe Valve should be higher than the main pipe. Otherwise, liquid drainage measures should be taken.
6. The outlet pipe of the Globe Valve that is discharged into the closed system should be connected at an angle of 45° along the direction of the medium flow at the top of the discharge main pipe to prevent the condensate in the main pipe from flowing back into the branch pipe and reduce the back pressure of the Globe Valve.
7. When there is a universal cut-off valve on the inlet and outlet pipelines of the Globe Valve, a single-gate
Gate Valve should be used and the lead seal should be opened. The
Valve Stem should be installed horizontally to prevent the valve plate from being corroded or loosened when the pin connecting the valve stem and the valve plate is corroded or loosened. decline. When the Globe Valve is equipped with a bypass valve, the valve should be sealed and closed.
The following aspects should be considered when selecting a Globe Valve:
(1) The structural form of the Globe Valve to be selected mainly depends on the process conditions of the equipment and the characteristics of the working medium. Under normal circumstances, most boilers and pressure vessels use Universal Valve. If the working medium of the container is toxic, flammable and explosive, a closed Globe Valve should be used. Boilers and high-pressure vessels, as well as medium and low-pressure vessels with large safety relief capacity and not too thick wall thickness, try to use full-open Globe Valve.
(2) Pressure range Globe Valve are designed and manufactured according to the nominal pressure standard series. Each Globe Valve has a certain working pressure range. When selecting, appropriate Globe Valve should be selected according to the maximum allowable working pressure of the boiler and
Pressure Vessel.
(3) The discharge capacity of the Globe Valve selected must be greater than the safe discharge capacity of the equipment. This can ensure that when the boiler or pressure vessel is overpressured, the Globe Valve can be opened to discharge part of the medium in time to prevent the pressure inside the device from continuing to rise.
The following points should be noted when setting up the Globe Valve:
(1) When there are gas and liquid two-phase materials in the container, the Globe Valve should be installed in the gas phase part.
(2) When the Globe Valve is used to discharge flammable liquids, the outlet of the Globe Valve should be connected to the accident storage tank. When the discharged materials are high-temperature combustibles, the receiving container should have corresponding protective facilities.
(3) Generally, Globe Valve can be vented on-site. The vent port should be more than 1 meter (m) above the operator and should not face open flames, spark-emitting locations and high-temperature equipment within 15 meters (m). The vent holes of Globe Valve of indoor equipment and containers should be led out of the roof and should be more than 2 meters (m) higher than the roof.
(4) When there is a isolation valve at the inlet of the Globe Valve, the isolation valve should be in a normally open state and sealed to avoid errors.
